1. Field of the Invention
This invention relates to insecticidal compositions effective for killing insects and more particularly, to an environmentally safe powdered insecticide bait composition for luring and killing a variety of scavenging pest insects and a method for preparing the composition. In a preferred embodiment of the invention, a commercially-prepared, dry pet food such as dog food is initially milled, ground or otherwise comminuted to a particle size between a 100 mesh and 400 mesh screen size. A pet food having a high fat content is preferred, since food of this character is more effective in attracting both German and American cockroaches, fire ants and other scavenging insects, than is food having a low fat content. Powdered boric acid having a particle size smaller than a 250 mesh screen is then blended with the pet food. Boric acid is used because it has a proven long-lasting residual cockroach-killing capability and is non-toxic to mammals in the indicated concentrations, including livestock and domestic animals such as cattle, sheep, horses, dogs, cats, as well as zoo and laboratory animals and the like, A powdered pyrethrin or pyrethroid killing ingredient, preferably a synthetic pyrethrin devoid of solvents, is next blended with the boric acid mixture, Synthetic pyrethrins exhibit very effective insect control, have little odor and, like boric acid, are non-toxic to mammals in the indicated concentrations, An absorbent clay drying agent having a particle size smaller than 250 mesh, is preferably blended with the mixture in sufficient quantity to insure flowability of the powdered mixture. The drying agent removes moisture from the pet food particles, preventing the mixture from clumping and thus enabling it to be freely flowable and easily dispensed from a container. The resulting non-toxic and easy-to-use, powdered mixture has been found to be very effective in attracting and eliminating not only American and German cockroaches, but also ants, scavenging beatles, crickets, earwigs, houseflies, termites and virtually any other type of scavenging insect.
2. Description of the Prior Art
Several compounds are known in the art for eliminating ants, cockroaches and other undesirable insects. U.S. Pat. No. 3,962,458, dated Jun. 8, 1976, to Michael S. Schrider, details a "Systemic Control of Ectoparasites With Pyrethroids", utilizing m-phenoxybenzyl esters of spirocarboxylic acids as systemic insecticidal and acaricidal agents for treatment of homothermic animals. U.S. Pat. No. 4,438,090, dated Mar. 20, 1984, to Alan D. Brite, discloses a "Method of Preparing an Insecticide Containing Boric Acid", including the steps of milling the boric acid to a desired particle size, blending the boric acid particles with magnesium stearate, silica gel or tricalcium phosphate, adding sucrose octa-acetate or denatonium benzoate, adding a non-white powdered pigment, and electrically charging the particles of the resulting insecticide mixture. U.S. Pat. No. 4,461,758, dated Jul. 24, 1984, also to Alan D. Brite, describes an "Insecticide Including Powdered Boric Acid", characterized by a mixture of powdered boric acid, sucrose octa-acetate or denatonium benzoate, magnesium stearate, silica gel or tricalcium phosphate, and a nonwhite powdered pigment. U.S. Pat. No. 4,759,930, dated Jul. 26, 1988, to Marc S. Granirer, et al, details "Insect Killing Compositions and Method of Killing Insects Employing a Synergistic Mixture of Pyrethrum, Eucalyptus, Rosemary and Peppermint". The compositions are characterized by a powder, including a mixture of pyrethrum and/or rotenone and one or more of the following: eucalyptus, rosemary, peppermint and boric acid. U.S. Pat. No. 5,047,424, dated Sep. 10, 1991, to George S. Puritch, et al, discloses an "Environmentally Safe Insecticide", including a mixture of monocarboxylic acids and their alkali metal salts and a pyrethroid compound.
An object of this invention is to provide an insecticide bait composition of low toxicity and extremely low application rate, for effectively killing a variety of undesirable insects.
Another object of this invention is to provide a powdered insecticide bait composition of minimum active ingredient, combined with extremely low application rate, which is substantially nontoxic, odorless, requires no solvents or other ingredients and includes commercial pet food, boric acid and a pyrethrin or pyrethroid killing ingredient.
Yet another object of this invention is to provide an environmentally safe, ready-to-use insecticide bait composition characterized by a fine, dry, readily-flowable powder which is easily dispensed from a selected container and includes commercial pet food, boric acid, a pyrethrin or pyrethroid and a clay drying agent.
An even further object of this invention is to provide a method for preparing an insecticide bait composition, including the steps of grinding, pulverizing or comminuting dry, commercial pet food into a flowable powder, mixing powdered boric acid with the pet food and blending a powdered pyrethrin or pyrethroid ingredient with the pet food and boric acid mixture.
Still another object of this invention is to provide a method for preparing a powdered insecticide bait composition, which includes the steps of milling or grinding and screening dry, commercial pet food, mixing a powdered synthetic pyrethrin or pyrethroid and powdered boric acid with the ground pet food as killing ingredients and adding a clay drying agent to the mixture to maintain the mixture in a dry, finely powdered, readily flowable state.